Total anthocyanin pigments increased from 74.7 to 317 mg/100 g fresh weight (FW) from underripe to overripe for Marion blackberries and from 69.9 to 164 mg/100 g FW for Evergreen blackberries. Total phenolics did not show a marked change with maturity with values slightly decreasing from underripe to ripe. Antioxidant activities, while increasing with ripening, also did not show the marked change that total anthocyanins exhibited. The impact of variation due to plots, subsampling, sample preparation, and measurement on Marion composition was examined in detail. Plot-to-plot and sample differences were the major contributors to variation, with sample preparation being an important contributor for some parameters. Measurement variation was a relatively small component of the total variation. Total anthocyanins for 11 blackberry cultivars ranged from 131 to 256 mg/100 g FW (mean = 198), total phenolics ranged from 682 to 1056 mg GAE/100 g FW (mean = 900), oxygen radical absorbance capacity ranged from 37.6 to 75.5 micromol TE/g FW (mean = 50.2), and ferric reducing antioxidant power ranged from 63.5 to 91.5 micromol TE/g FW (mean = 77.5).

The polyphenolics in aqueous extracts of Marion (Rubus sp. hyb) and Evergreen (Rubus laciniatus) blackberries and blackberry seeds were isolated by solid-phase extraction using C 18 cartridges and polyamide mini-column chromatography, and characterized using reversed-phase high-performance liquid chromatography/diode array spectral techniques. Flavonols (primarily quercetin glycosides) were the major phenolics in berries, whereas procyanidins (catechin and epicatechin) and ellagic acid derivatives predominated in seeds. No flavonols were found in seeds. Evergreen berries contained higher level of epicatechin, ellagic acid derivatives, and flavonols than Marion berries, whereas Marion berries and seeds were higher in anthocyanins, total phenolics, and antioxidant properties as measured by oxygen radical absorbance capacity and ferric reducing antioxidant power.

: The sediment in a commercial reconstituted ‘Evergreen’ blackberry (Rubus laciniatus L.) juice concentrate was found to be composed of ellagic acid, protein, and other unidentified compounds. The qualitative tannin and protein‐tannin haze test indicated that the sediment was predominantly tannin or protein‐tannin complexes. Nitrogen determination showed the sediment to be 6.69%± 2.21% protein on a dry‐weight basis. Almost all of the extractable material was identified as ellagic acid by high‐performance liquid chromatography and liquid chromatography‐mass spectrometry. The ellagic acid content of the wet sediment was 0.05 g/100 g, whereas it was 7.41 g/100 g in freeze‐dried sediment. Tannase enzyme did not significantly decrease the concentration of ellagitannins in Marion blackberry (Rubus spp. Hyb.) juice in this study.

The optimization of antioxidant and anti-tyrosinase activity during jellyfish hydrolysate preparation was studied using a response surface methodology (RSM) with a face-centered composite design. The influence of the hydrolysis duration and the enzyme concentration on the IC50 of the DPPH and ABTS radical scavenging activity, ferric-reducing antioxidant power (FRAP), the degree of hydrolysis (DH), yield, and the IC50 value of tyrosinase inhibitory activity were determined. The optimum conditions for the production of jellyfish hydrolysate using alcalase (JFAH), flavourzyme (JFFH), or papain (JFPH) were achieved at hydrolysis times of 360, 345, or 360 min, respectively, and at an enzyme concentration of 5.0%. JFFH had the highest antioxidant and tyrosinase inhibitory activity. JFAH, JFFH, and JFPH concentrations of 2.5 mg/mL resulted in HaCaT cells (IC80) having a survival rate of 80%. The amino acid profile of JFFH contained about 43% hydrophobic and 57% hydrophilic amino acids, comprising Gly, Cys, Glx, Asx, which were dominant. The isolation of a peptide fraction from JFFH was carried out using ultrafiltration membranes (10, 3, and 1 kDa) and gel filtration chromatography. Fraction-III (1–3 kDa) showed the highest antioxidative and tyrosinase inhibitory activity.

This research aimed to enhance the physicochemical and antioxidant properties of dried whole longan fruit using Maillard reaction or non-enzymatic glycosylation (glycation) in a moist-dry-heating system at 60 C with approximately 75% relative humidity for 5-50 days. During Maillard reaction, the browning index (BI) of the fruits increased significantly while lightless, redness and yellowness decreased. Interestingly, the rare sugars especially D-psicose and D-allose gradually increased by 2-3 folds when compared to the initial Maillard reaction. The development of D-mannose was additionally established through the glycation. The degree of glycation increased with the decrease of free amino acid, suggesting that conjugation of sugar with amino acids was involved. SDS-PAGE confirmed that the high molecular weight (HMW) of conjugated sugar-amino acid was the Maillard reaction product. The antioxidative properties including DPPH and ABTS radical scavenging activities, also ferric reducing antioxidant power (FRAP) were also increased as Maillard reaction progressed, which showed the activities in the range of 43.2-94.1 mg GAE/100 g dry basis, 0.23-3.09 g TE/100 g dry basis, and 0.35-5.95 g FeSO 4 /100 g dry basis, respectively. This study demonstrated a practical approach of Maillard reaction for the development of dried longan fruit with high antioxidative properties.

Sea cucumber is rich in protein that can be used to prepare a potential derived bioactive peptide for antioxidant and protective effect against UV-B induced skin cell damage. This study aimed to optimize preparation of sea cucumber hydrolysate with both UV-B protective and antioxidant activities using three commercial enzymes using response surface methodology (RSM) with a face-centered central composite design (face- centered CCD). Hydrolysis time and concentration of enzyme effects on the degree of hydrolysis (DH), yield, antioxidant and UV-B protective activities of sea cucumber hydrolysates were determined. The optimum conditions for sea cucumber hydrolysis using papain (SCP), alcalase (SCA), or flavourzyme (SCF) were 3.6, 5.0, and 4.1% (w/w protein), respectively, and a hydrolysis time of 360 min. The resulting hydrolysates had a DH of 81-91%, yield of 13-14%, IC50 for DPPH radical scavenging activity of 0.3-4.1 mg/mL, FRAP of 0.5-0.6 mmol FeSO4/mL, and IC50 for ABTS radical scavenging activity of 1.3-1.6 mg/mL. The UV-B protective activity was reported as the HaCaT cell viability percentage after UV-B treatment. The SCP, SCA, and SCF hydrolysates showed 72.4, 74.5, and 71.3% cell viability, respectively. The concentration of hydrolysates with 80% survival of HaCaT cells was 0.21, 0.15 and 0.20 mg/mL for SCP, SCA and SCF, respectively. Thus, the SCP was selected for bioactive peptide isolation and characterization. The SCP contained hydrophilic and hydrophobic amino acids of 42.4 and 57.6%, respectively. The ultrafiltration and Sephadex G-25 gel filtration chromatography were done for peptide isolation from the SCP. Six potential peptides were identified using LC-MS/MS as Leu-Val-Asn-Glu-Leu-Thr-Glu-Phe-Ala-Gln (1163 Da), Leu-Val-Asn-Glu-Val-Thr-Glu-Phe-Ala-Gln (1149 Da), Phe-Val-Asp-Ser-Ser-Ala-Thr-Thr (826 Da), Phe-Asn-Asp-Leu-Gly-Ala-Trp (821 Da), Phe-Pro-Asp-Thr-Thr-Thr-Leu (793 Da), and Lys-Phe-Gly-Glu-Gly-Lys (664).

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Vitamin C is a water‐soluble antioxidant used in the food industry despite its well‐known instability. This study aimed to investigate the effectiveness of sweet basil methanolic and ethanolic extracts in delaying vitamin C degradation in a model solution and in guava juice during storage (25, 35, and 45 °C). Solutions containing methanolic extracts (0.5–2%) had higher vitamin C content than controls at all times and temperatures. The protective effect depended on extract concentration, storage time, and storage temperature (p < .01). Ethanolic extracts were only significantly beneficial at 35 and 45 °C (p < .05). At these temperatures, methanolic extracts were better at preserving vitamin C in the model solution and the guava juice. The vitamin C was 38.6 and 45.3% higher than the control with a 3% methanolic extract in guava juice after 1 week at 35 and 45 °C, respectively. Practical applications Vitamin C has been used extensively in food, supplement, pharmaceutical, and cosmetic industries as a nutrient as well as a potent antioxidant. The major limitation is its instability towards heat, light, and oxidation. This study offered a natural solution to vitamin C preservation in foods. It also provided basis for future development of natural preservative for oxidation sensitive compounds in foods and supplement products.